A trunking system is an advanced mobile communication dispatch system. The so-called trunking system means that available channels owned by the system can be shared by all users of the system and it has automatic channel selecting function. And the trunking system is a widely used wireless delegation communication system with high efficiency and low cost for sharing resources, burdening costs and sharing channel equipments and services. The trunking system has a high requirement on rapid call establishing. In addition, because of the specialty of the client groups, the requirement of call-through rate is high.
The trunking systems are mostly calling system which is centrally controlled through known PMN public mobile network, such as GSM network, with incorporated dispatching sub-systems.
Presently, a novel distributed trunking system is proposed which does not pass through public mobile network and has an independent calling system. The structure of the system is shown in FIG. 1, comprising trunking radio nodes (TRN) 10, a trunking dispatching center (TDC) 20, a trunking location register (TLR) 30, an application service (AS) 40 and a dispatching console 50. It further comprises a voice gateway (VGW) 60, a data gateway (DGW) 70 and a trunking interworking node (TIN) 80.
The user equipment (UE) 90 accesses the network by air interfaces of the TRN 10. And the UE 90 accessed into the TRN 10 is performed with mobile management and calling control by the TRN 10. The related information of the UE 90 accessed into the TRN 10 is notified to TDC 20, TLR 30 and other TRN 10, other UE 90 information sent by other TRN 10 is obtained and saved by the TRN 10. TDC 20 performs dispatch control to the UE 90s based on the dispatching of the dispatching console through the TRN 10, TLR 30 in the network. TLR 30 stores the related information of UE 90 for providing information to TRN 10 and assisting TRN 10 in the mobile management of the UEs. AS 40 manages the related information of UE 90s stored by the TLR 30. The dispatching console 50 is an equipment for performing dispatching control and service management of the UE 90s in the trunking communication network, mainly finishing the dispatching command of trunking call. VGW 60 achieves the interconnection and voice communication of the TRN 10, TDC 20, TLR 30 in the system with the PSTN public switched telephone network and/or PLMN public land mobile network 100. DGW 70 achieves the interconnection and data communication of the TRN 10, TDC 20, TLR 30 in the system with the external service network/data server 110. TIN 80 achieves trans-network communication between different trunking networks in the system.
In public mobile network, the network side initiates paging to an UE based on the location area/route area information of the called UE saved. However, under special circumstances, because the quality of the wireless network is inferior or the location area/route area where the UE is located changes whereas the UE does not report timely, thus the UE can not be paged at the network side.
Secondary paging solution is adopted in the public mobile network to avoid the occurrence of the above cases. The so-called secondary paging means: the network side initiates paging to the called UE in the location area/route area based on the saved location area/route area information of the called UE; if the called UE has moved into a new location area/route area without timely reporting the new location information to the network side, the called UE can not be paged in the original location area/route area by the network side. At this time, the network side automatically extends the paging range and secondarily pages the called UE at location areas/route areas adjacent to the original location area/route area, thus enhancing paging success rate and the call-through rate.
The problem of paging the trunking system user through the public mobile network lies in: if a primary paging is adopted, the paging range for the UE is limited, which only points to one location area/route area; if a secondary paging is adopted, the paging time delay is relatively long. In addition, whether a primary paging or a secondary paging is used, it can only be paged in the location areas/route areas managed by the same core network, which does not support trans-core network paging.
For the distributed trunking system, no specific paging method is proposed.